If I recall correctly, didn't we find in 2008 approximately where the price of gas becomes elastic? I think it was around $4.25/gal at the time (but this info has been sitting in my brain for 14 years, so I'm not confident). I can't imagine much has changed since then, even if my numbers are slightly off. We will find a point at which people start to migrate to cars that are cheaper to operate (outside of the luxury vehicle market). In 08 I bought a manual Corolla that got about 40 mpg if driven non-aggressively. I was in grad school and commuting daily from my apartment to my teaching gig to the lab, a ~40 mi round trip. I'm sure they still get the same approximate gas mileage.

I know we all hate to see oil tycoons getting tycoonier, but the fact is that high fuel prices are what drive market change. So if global warming is a bigger concern than profit taking, then you should root for high gas prices to stay. I own two cars, a V60 Polestar that demands 93 octane, and a Sierra that runs on diesel. Both are at about $6/gal around here. I'm upper middle class and I swallow hard every time I have to fill up. It hurts, but it's actually probably much closer to what they should cost.